Re:Next week: Lumbar Puncture at Home
on
Build Your Own ECG
·
· Score: 1
I remember a gadget to do something like that. Called a trepanator. They had it as a prop for the friday the 13th TV series. It took the spinal juice from the victim, and transfered it to some other person. It was some sort of cursed relic used to extract the victims manna or whatever.
I suppose that is the one tricky thing with EKGs. Most people who have those hooked up to em may have to get zapped with the defib unit. Even if you block the DC with caps, theres always AC, RF noise, etc generated.
Once we get rid of you troublesome doctors helping people cheat death, we can go back to darwinism and actually improve the gene pool. Or possibly get to work on something "EVIL" like human genetic engineering. Your parents and grandparents have heart problems, tweak the DNA a bit, and at least your children wont. Would have to be an offshore enterprise, and made illegal by governments. People don't like the work, too bad, they broke the law to do it.
Theres nothing really stopping someone from being their own doctor. You have plenty of sights online that cover actual pre-med and medical school training. And you can also get vetrinary supplies at any farm store. And plenty of cast off medical gadgets at surplus/junk auctions are available to be cleaned up,and repaired. Ya want low costs, there ya go. Ya want to be sure that you'll never have something bad happen ? haha, unlikely. Even with the incessant whining of the neurotic mommies of the world for a more and more well padded rubber room society, people will still die for no good reason randomly.
The electric chair was Edison's idea, which is why its such a lame kludge. Mostly it stuns the nervous system, and sort of bakes the person alive. You could probably revive some of these people to the point the heart would work. For a little while at least.
The new system uses barbituates to shut off the brain and relax the system, potasium chloride to turn off the heart, and something else to stop the diaphram from working. Much cleaner, and minimal chance of failure since its tripple redundant.
Well, I did get free electroshock therapy from when a fence wire hooked up to a 100 mile horse fencer touched my temple. You can't feel too depressed when stunned and dazed, so I guess it was effective.
Having played with soundforge, I'd say try that. Seems like it would be ideal for the waveform you are dealing with. You could trigger on the "pop and clicks" dirtying up your wave form, or anything off tempo.
I think the actual latest version sells for like $500. But I'm sure there are older cheaper copies around for much less. maybe even a demo version still without the real necessary stuff like the wah wah pedal effect enabled.;)
you could even combine a video channel with it and see the patient turning purple, white, deep red and see which wavefrom watched it.
There always a problem with using just raw data. It has to do with how the machine will see something , and how a human will see it. A human neural net learns how to see what is different. And theres a whole lot to that.
A machine has to be told how to see what is really different, and what is just noise and natural variations. To do this, you have to reverse engineer yourself to some degree.
When I'm poking around some circuit, I can blow by a whole bank of say 3 megohm resistors. Up to say 100 a minute at top speed. The meter if programmed to blip at ever out of range one would false hit like crazy even if they were good.
I know whats good and bad based on past history, and knowing how these things go bad. If I get a reading of 4.5 megaohm, I know its probably probe error, solder oxidation, conformal coating. If I see 6 megohm, and I'm pressing down with a freshly sharpened probe tip, I know that sucker is bad. Or I may get variable readings if I'm going too fast and the auto ranging on the meter is snarling up the sampling speed.
All that is a constantly changing set of filters that allows a human to use a less than perfect tool. To get this built in so it works is tricky, to get it to the point where is works quickly and be tolerant of less than carefull users gets to be neerly impossible.
Which gets back to the original problem. Is the actual data any good. To a human, you won't see that the op amps are getting half the voltage because the paste is dry, and the automatic gain compensated by filling the screen with the waveform anyway. That's because you are looking for a hiccup in some QRS waveform(or whatever) and not seeing that you've got clipping somewhere in the circuit from too much gain.
So then you take data on a good day, new paste shipment, better probes, different machine. All clean data. Then you have a machine look at the stored data, and the machine trys to filter out sampling error junk, but then, a QRS hiccup looks like sampling noise, artifacts, etc. So you play it safe, and trigger on all the false hits.
Or you can do all sorts of neat tricks more appropriate for soundforge or pro tools, but then comes the problem, the user, that being the doctor or whoever, does not know how you did that. They don't know if your tool will filter out a hiccup for a particular condition. Even if it was done in colaboration with the prime users.
So you end up with a crude tool errors and all.
Of course, if you want to plug your EKG results into soundforge, you could probably use it to sift and sort in an automated way. But thats a personal initiative thing, theres no easy way you could sell a product to do that for what you are doing specifically.
Part of the problem is that its a limited tool. The signal has to get through all sorts of highly varied tissue, get sorted out by the op amps, and then be displayed.
The machine has no circuitry to say, check probe number 4s connection, or paste dried out on probes 1 and 3.
Now if you had a way to image the whole heart with
ultrasound, and then combine that with what the electrical signals were telling you, maybe a blood pressure readout, blood oxygen sensor, and whatever other gadgets, and get that all down to where is compact and unobtrusive enough that it doesn't drive the victim, er patient crazy, then you'll have something where a machine might be able to do a lot of the work.
To get a computer to look at a wafeform and break it down into the PQRS designations at highly varible speeds, and then subdivide each and weigh what was what could be interesting. Deffinately an app for fuzzy or neural net logic.
But its hard to say just how far that could go. For an experience cardiologist its a matter of looking at it, and letting the brain do its work.
Doing this in circuitry would get interesting. I suppose you might be able to add more probe wires to get more signal to work with.
But the machine has no way of knowing that the signal is off because the intern who wired up that patient is a klutz.
You could do event triggering to help index when a heart was having problems though. So you would reduce some of the workload.
EEGs usually do require that they grind the probes and the paste into your scalp pretty good.
Seems that skin works quite well even against megavoltages of lightning blasts. Otherwise noone would ever survive them.
Well now, there also lies a problem. What really causes these diseases like MS, Parkinsons, Huntingtons, and the whole other wide selections of nightmare neurological diseases that seem to be only on the rise in industrial countries ?
One would suspect that the things we use to maintain our high standards of living on occasion backfire and horrbily mame someone else.
And on top of this our fine set of values says that these people cannot be allowed to choose to end their lives, no matter how horrible the condition. In fact, they take great care with huntingtons patients to make sure they don't take their lives and be allowed to miss one minute of non-stop torment.
And they've also banned fetal cell and cloning research that might help to cure some of these nightmare diseases. If some other nation comes up with a cure, or derives it from that research either you stay in the USA and suffer, or pack your bags and leave for good, because if they find out you were cured with a banned treatment you'll land yourself in jail for many years.
This law was put into action by the same well meaning christian folks who say that assisted suicide is wrong, but the death penalty is just great.
So you see, it's these people that are so God fearing that are there to help their fellow man stay nailed to the cross for as long as possible, and make sure that their fellow americans pay for it all.
So if you are diagnosed with a nightmare neurolgical disease, your best solution is to start to killing people in a pro death penalty state. Then maybe you'll get fried before the symptoms are too bad.
You could probably pull it off in some third world country. Less RF in those places to mess with bad op amps.
If you want to be totally anal about it, not that any of the slashdot crowd would be that way, you could add in opto isolators, grounded probe lines, all sorts of other things.
Or you could partially crib the design of another device out there. A handheld box you put against your chest that data logs the electrical signals of you heart for when you have an arrythmia or whatever else. Then the patient sends in the data by putting the device up to the phone which transmits the signal as audio, probably stretched out several times so they wont lose fine data points to line noise.
This was a fairly good improvement over the previous device which was something you wore on a belt that was wired up with all the probe lines and worn for 2-3 days at a time. That device probably should have also had an audio indexing track so the patient could say what they were doing such as, about to lift these 80 pound sacks of concrete, balancing the checkbook, uh oh salted fatback for dinner AGAIN!
Now all we need the plans for is a good russian sleep device, or a brain tuner. Now theres something that requires attention to detail. But if something goes really wrong, at least you wont be depressed for a good half year.
hehe. been there, done that. But not exactly in that fashion. I actually had an audience. I had bottled a beer that was mostly finished fementing. Capped it, and put it in the trunk. Not usually a problem since its usually overcast around these parts. But it was real sunny before the homebrew meeting. The roads in the city are also well cratered. So I get to the meeting, fridge the beer for about 30 min. Time comes to get it out and pour it into the pitcher. When I go to open it the cap bounces off the ceiling , the bottle next to it explodes, and the fluid follwing the first cap splashes off the ceiling and gets the guy behind me. I was the only one to get nicked with a glass fragment amazingly.
Things like this tend to happen though, although few will ever admit that it happened to them if they can help it.
The FBI really should stop hiring scizophrenics and retards. Anyone who owns.45 automatic can take out as many people in armor as they have rounds in the gun. The 1911.45 automatic was the final nail in the coffin of the cavalry since it will knock off a horse just as well as the rider.
Theres no need for super high grade steels in SCA because the goal is not to go out and KILL people.
If you want to be some sort of nut it would not take a whole lot skill wise to spec some metals and make the ultimate slashes through anything sword.
Forget being authentic, you aren't going to be apprenticed at 13, and work with a team producing armor until you die of prevntable disease at 45.
SCA people do these things for fun. And the medeval world in reality was no great thrill. If you are totally bound and determined to live like an animal, there are still many places on earth where you can go and do just that.
Don't get too cranky there old dude, might burst another blood vessel and have to put off that mid life crisis.
There's a place for people who are washed up, useless, and have no skills, and that place is called City Council.
You can see plenty of mainframes at scrapyards around the US. Most of those probably died due to people storing the dead mainframe operators in the guts and forgetting them there for years.
Maybe they'll have to get those guys who worked on the delta clipper into the loop after they've fired the ones who crashed it, the ones who did the faster, better, cheap, fail at the last moment probes, and the people who decided eco friendly foam the breaks off and rips up the heating tiles was a good idea.
By then, you'll have to layoff the 80% who are only mildly incompetant.
And after that, you'll have a few dozen left who might be able to help build a new space agency.
Well now, that just goes to show how crazy those people in fort worthless are. First the class action suit for not paying the slaves, er retail employees for overtime and now this. For more amusing antics relating to the Shack, check out Radioshacksucks.com for many more amusing tales of angst.
If you work with high voltage devices, you work with only one hand at a time. Microwave techs occasionally slip up and touch live 4000v current.
You'll survive typically, if you alse remembered
to set the timer for only 15-20 secs.
The fact that it's also DC being fed to the magnetron also helps a bit, unless you touched ahead of the voltage doubler segment. Either way, you can forget using that arm much for a day or two.
In the event that you "kill" yourself, you can be revived with CPR if your co-workers know whats what, takes up to a half hour or an hour until the nerves in the heart start working again sometimes.
You would have to ban private ownership of microwave ovens to eliminate herf gun parts. The genie is out of the bottle. The only thing that will save you is the inverse square law and the fact that people capable of rigging up a high voltage high current microwave device without killing themselves are relatively rare.
The level of knowledge and common sense required to build one also tends to rule out anyone stupid enough to die for their religious quirks being able to make one.
I suspect though, that if you left your boomer stereo going in the car while you weren't in it, the risks of getting your harware nuked by an angry nerd with a herf are pretty good.
If you really want to cause some dammage you need a big grid of magnetrons, 8x8 or 12x12 coupled to a dish used to focus the beams into one beam.
Ideally you would have one big doubler going up to a voltage rating depending a maximum voltage rating that could be handled by the magnetron for say 300 bursts, and then feeding capacitor banks for each magnetron.
When the caps got to full charge, you could trip a bank of thyristors to fire the array. You would only need to keep the filaments going during charging. This system would allow you to operate off only a 4kW supply current, and would not require complete independant power supplies (half wave doublers, transformer,etc).
The only way you could really pull this off would be to collect junked microwaves for about a year or more to get the necessary collecion of working capacitors, diodes, and magnetrons.
Would be best to have it as a mobile rig because after firing,your EM signature will likely trip alarms on who knows how many military systems.
The only safe testing would be inside a well grounded metal screened enclosed area(aka a faraday cage) unless you are willing to incur the wrath of numerous govt agencies.
Slashdot Mirror
I remember a gadget to do something like that. Called a trepanator. They had it as a prop for the friday the 13th TV series. It took the spinal juice from the victim, and transfered it to some other person. It was some sort of cursed relic used to extract the victims manna or whatever.
I suppose that is the one tricky thing with EKGs. Most people who have those hooked up to em may have to get zapped with the defib unit. Even if you block the DC with caps, theres always AC, RF noise, etc generated.
Once we get rid of you troublesome doctors helping people cheat death, we can go back to darwinism and actually improve the gene pool. Or possibly get to work on something "EVIL" like human genetic engineering. Your parents and grandparents have heart problems, tweak the DNA a bit, and at least your children wont. Would have to be an offshore enterprise, and made illegal by governments. People don't like the work, too bad, they broke the law to do it.
Theres nothing really stopping someone from being their own doctor. You have plenty of sights online that cover actual pre-med and medical school training. And you can also get vetrinary supplies at any farm store. And plenty of cast off medical gadgets at surplus/junk auctions are available to be cleaned up,and repaired. Ya want low costs, there ya go. Ya want to be sure that you'll never have something bad happen ? haha, unlikely. Even with the incessant whining of the neurotic mommies of the world for a more and more well padded rubber room society, people will still die for no good reason randomly.
The electric chair was Edison's idea, which is why its such a lame kludge. Mostly it stuns the nervous system, and sort of bakes the person alive. You could probably revive some of these people to the point the heart would work. For a little while at least. The new system uses barbituates to shut off the brain and relax the system, potasium chloride to turn off the heart, and something else to stop the diaphram from working. Much cleaner, and minimal chance of failure since its tripple redundant.
Well, I did get free electroshock therapy from when a fence wire hooked up to a 100 mile horse fencer touched my temple. You can't feel too depressed when stunned and dazed, so I guess it was effective.
Having played with soundforge, I'd say try that. Seems like it would be ideal for the waveform you are dealing with. You could trigger on the "pop and clicks" dirtying up your wave form, or anything off tempo. I think the actual latest version sells for like $500. But I'm sure there are older cheaper copies around for much less. maybe even a demo version still without the real necessary stuff like the wah wah pedal effect enabled. ;)
you could even combine a video channel with it and see the patient turning purple, white, deep red and see which wavefrom watched it.
There always a problem with using just raw data. It has to do with how the machine will see something , and how a human will see it. A human neural net learns how to see what is different. And theres a whole lot to that. A machine has to be told how to see what is really different, and what is just noise and natural variations. To do this, you have to reverse engineer yourself to some degree. When I'm poking around some circuit, I can blow by a whole bank of say 3 megohm resistors. Up to say 100 a minute at top speed. The meter if programmed to blip at ever out of range one would false hit like crazy even if they were good. I know whats good and bad based on past history, and knowing how these things go bad. If I get a reading of 4.5 megaohm, I know its probably probe error, solder oxidation, conformal coating. If I see 6 megohm, and I'm pressing down with a freshly sharpened probe tip, I know that sucker is bad. Or I may get variable readings if I'm going too fast and the auto ranging on the meter is snarling up the sampling speed. All that is a constantly changing set of filters that allows a human to use a less than perfect tool. To get this built in so it works is tricky, to get it to the point where is works quickly and be tolerant of less than carefull users gets to be neerly impossible. Which gets back to the original problem. Is the actual data any good. To a human, you won't see that the op amps are getting half the voltage because the paste is dry, and the automatic gain compensated by filling the screen with the waveform anyway. That's because you are looking for a hiccup in some QRS waveform(or whatever) and not seeing that you've got clipping somewhere in the circuit from too much gain. So then you take data on a good day, new paste shipment, better probes, different machine. All clean data. Then you have a machine look at the stored data, and the machine trys to filter out sampling error junk, but then, a QRS hiccup looks like sampling noise, artifacts, etc. So you play it safe, and trigger on all the false hits. Or you can do all sorts of neat tricks more appropriate for soundforge or pro tools, but then comes the problem, the user, that being the doctor or whoever, does not know how you did that. They don't know if your tool will filter out a hiccup for a particular condition. Even if it was done in colaboration with the prime users. So you end up with a crude tool errors and all. Of course, if you want to plug your EKG results into soundforge, you could probably use it to sift and sort in an automated way. But thats a personal initiative thing, theres no easy way you could sell a product to do that for what you are doing specifically.
Part of the problem is that its a limited tool. The signal has to get through all sorts of highly varied tissue, get sorted out by the op amps, and then be displayed. The machine has no circuitry to say, check probe number 4s connection, or paste dried out on probes 1 and 3. Now if you had a way to image the whole heart with ultrasound, and then combine that with what the electrical signals were telling you, maybe a blood pressure readout, blood oxygen sensor, and whatever other gadgets, and get that all down to where is compact and unobtrusive enough that it doesn't drive the victim, er patient crazy, then you'll have something where a machine might be able to do a lot of the work.
To get a computer to look at a wafeform and break it down into the PQRS designations at highly varible speeds, and then subdivide each and weigh what was what could be interesting. Deffinately an app for fuzzy or neural net logic. But its hard to say just how far that could go. For an experience cardiologist its a matter of looking at it, and letting the brain do its work. Doing this in circuitry would get interesting. I suppose you might be able to add more probe wires to get more signal to work with. But the machine has no way of knowing that the signal is off because the intern who wired up that patient is a klutz. You could do event triggering to help index when a heart was having problems though. So you would reduce some of the workload.
EEGs usually do require that they grind the probes and the paste into your scalp pretty good. Seems that skin works quite well even against megavoltages of lightning blasts. Otherwise noone would ever survive them.
Well now, there also lies a problem. What really causes these diseases like MS, Parkinsons, Huntingtons, and the whole other wide selections of nightmare neurological diseases that seem to be only on the rise in industrial countries ?
One would suspect that the things we use to maintain our high standards of living on occasion backfire and horrbily mame someone else.
And on top of this our fine set of values says that these people cannot be allowed to choose to end their lives, no matter how horrible the condition. In fact, they take great care with huntingtons patients to make sure they don't take their lives and be allowed to miss one minute of non-stop torment.
And they've also banned fetal cell and cloning research that might help to cure some of these nightmare diseases. If some other nation comes up with a cure, or derives it from that research either you stay in the USA and suffer, or pack your bags and leave for good, because if they find out you were cured with a banned treatment you'll land yourself in jail for many years.
This law was put into action by the same well meaning christian folks who say that assisted suicide is wrong, but the death penalty is just great.
So you see, it's these people that are so God fearing that are there to help their fellow man stay nailed to the cross for as long as possible, and make sure that their fellow americans pay for it all.
So if you are diagnosed with a nightmare neurolgical disease, your best solution is to start to killing people in a pro death penalty state. Then maybe you'll get fried before the symptoms are too bad.
You could probably pull it off in some third world country. Less RF in those places to mess with bad op amps. If you want to be totally anal about it, not that any of the slashdot crowd would be that way, you could add in opto isolators, grounded probe lines, all sorts of other things. Or you could partially crib the design of another device out there. A handheld box you put against your chest that data logs the electrical signals of you heart for when you have an arrythmia or whatever else. Then the patient sends in the data by putting the device up to the phone which transmits the signal as audio, probably stretched out several times so they wont lose fine data points to line noise. This was a fairly good improvement over the previous device which was something you wore on a belt that was wired up with all the probe lines and worn for 2-3 days at a time. That device probably should have also had an audio indexing track so the patient could say what they were doing such as, about to lift these 80 pound sacks of concrete, balancing the checkbook, uh oh salted fatback for dinner AGAIN! Now all we need the plans for is a good russian sleep device, or a brain tuner. Now theres something that requires attention to detail. But if something goes really wrong, at least you wont be depressed for a good half year.
you just need to hook up that 455 to a generator and use it to power your toxitherm 3000 mercury vapor arc furnace and wort heater.
hehe. been there, done that. But not exactly in that fashion. I actually had an audience. I had bottled a beer that was mostly finished fementing. Capped it, and put it in the trunk. Not usually a problem since its usually overcast around these parts. But it was real sunny before the homebrew meeting. The roads in the city are also well cratered. So I get to the meeting, fridge the beer for about 30 min. Time comes to get it out and pour it into the pitcher. When I go to open it the cap bounces off the ceiling , the bottle next to it explodes, and the fluid follwing the first cap splashes off the ceiling and gets the guy behind me. I was the only one to get nicked with a glass fragment amazingly. Things like this tend to happen though, although few will ever admit that it happened to them if they can help it.
The FBI really should stop hiring scizophrenics and retards. Anyone who owns .45 automatic can take out as many people in armor as they have rounds in the gun. The 1911 .45 automatic was the final nail in the coffin of the cavalry since it will knock off a horse just as well as the rider.
Theres no need for super high grade steels in SCA because the goal is not to go out and KILL people. If you want to be some sort of nut it would not take a whole lot skill wise to spec some metals and make the ultimate slashes through anything sword. Forget being authentic, you aren't going to be apprenticed at 13, and work with a team producing armor until you die of prevntable disease at 45. SCA people do these things for fun. And the medeval world in reality was no great thrill. If you are totally bound and determined to live like an animal, there are still many places on earth where you can go and do just that.
Don't get too cranky there old dude, might burst another blood vessel and have to put off that mid life crisis. There's a place for people who are washed up, useless, and have no skills, and that place is called City Council.
You can see plenty of mainframes at scrapyards around the US. Most of those probably died due to people storing the dead mainframe operators in the guts and forgetting them there for years.
Maybe they'll have to get those guys who worked on the delta clipper into the loop after they've fired the ones who crashed it, the ones who did the faster, better, cheap, fail at the last moment probes, and the people who decided eco friendly foam the breaks off and rips up the heating tiles was a good idea. By then, you'll have to layoff the 80% who are only mildly incompetant. And after that, you'll have a few dozen left who might be able to help build a new space agency.
Well now, that just goes to show how crazy those people in fort worthless are. First the class action suit for not paying the slaves, er retail employees for overtime and now this. For more amusing antics relating to the Shack, check out Radioshacksucks.com for many more amusing tales of angst.
You wanna do a driveby you need a bad boy reflex klystron with these specs.
Output power of microwave oscillations, kW
70 -100
Operating frequency, MHz
45%
Operating mode
continuous or modulated within the frequency range of klystron
Running cycle duration, min
>60
Mean-time-to-first-failure, h
>1000
Number of running cycles
>800
Cooling
Liquid
Average temperature of coolant, Ñ
35
Positive pressure, gauge atmosphere
6 - 8
Coolant flow rate in operating mode, l/min
110
Coolant flow rate in resonator unit channel and in output
waveguide, l/min
>30
Accelerating voltage of amplifier, kV
25 - 35
Focusing magnetic field, T
0,15 - 0,25
Dimensions, mm
550 x 600 x 950
Weight ("dry"), kg
150
available from http://lakai.everdesk.com/mobile.htm
Course you'll need a health diesel electric engine to power it, or maybe you could mod one of those hybrid cars to power the beastie.
If you work with high voltage devices, you work with only one hand at a time. Microwave techs occasionally slip up and touch live 4000v current. You'll survive typically, if you alse remembered to set the timer for only 15-20 secs. The fact that it's also DC being fed to the magnetron also helps a bit, unless you touched ahead of the voltage doubler segment. Either way, you can forget using that arm much for a day or two. In the event that you "kill" yourself, you can be revived with CPR if your co-workers know whats what, takes up to a half hour or an hour until the nerves in the heart start working again sometimes.
You would have to ban private ownership of microwave ovens to eliminate herf gun parts. The genie is out of the bottle. The only thing that will save you is the inverse square law and the fact that people capable of rigging up a high voltage high current microwave device without killing themselves are relatively rare. The level of knowledge and common sense required to build one also tends to rule out anyone stupid enough to die for their religious quirks being able to make one. I suspect though, that if you left your boomer stereo going in the car while you weren't in it, the risks of getting your harware nuked by an angry nerd with a herf are pretty good.
If you really want to cause some dammage you need a big grid of magnetrons, 8x8 or 12x12 coupled to a dish used to focus the beams into one beam. Ideally you would have one big doubler going up to a voltage rating depending a maximum voltage rating that could be handled by the magnetron for say 300 bursts, and then feeding capacitor banks for each magnetron. When the caps got to full charge, you could trip a bank of thyristors to fire the array. You would only need to keep the filaments going during charging. This system would allow you to operate off only a 4kW supply current, and would not require complete independant power supplies (half wave doublers, transformer,etc). The only way you could really pull this off would be to collect junked microwaves for about a year or more to get the necessary collecion of working capacitors, diodes, and magnetrons. Would be best to have it as a mobile rig because after firing ,your EM signature will likely trip alarms on who knows how many military systems.
The only safe testing would be inside a well grounded metal screened enclosed area(aka a faraday cage) unless you are willing to incur the wrath of numerous govt agencies.